Fourteen years, 300 miles...
Special circumstances.
Dodge Ram running on propane, used for getting firewood from the forest.

I changed the oil before we sold it, the oil was still clean, and I burned it in the fuel tank of a Chevette Diesel.

Chevette Diesel
http://www.google.com/search?hl=en&q=Chevette+Diesel&btnG=Google+Search